The invention relates generally to line drivers and more specifically to minimizing power dissipation in line drivers driving DSL (digital Subscriber Line) connections to network terminals.
In line drivers in a central office for driving DSL connections of unknown lengths to network terminals, the supply voltage to driving transistors in the final stage of the line drivers, is set to a fixed value to give a fixed line driver output voltage in order to secure data transmission to the network terminals irrespective of the length of the DSL connections.
There is a desire to put more and more line drivers on one and the same printed circuit board.
With more and more line drivers on the same printed circuit board, there is a risk that the power dissipation from the line drivers will be too high on the printed circuit board.
The object of the invention is to minimize the power dissipation of the line drivers on such printed circuit boards in order to be able to put more line drivers on one and the same printed circuit board.
This is attained in accordance with the invention by reducing the power spectral density to a lowest possible value that enables transfer of data and in response hereto reducing the supply voltage of the line drivers.
Hereby, also the power dissipation of the line drivers will be minimized.